public PCA(double[][] trainingSet, List <string> labels, int numOfComponents)
{
this.trainingSet = trainingSet;
this.labels = labels;
this.numOfComponents = numOfComponents;
this.meanMatrix = Accord.Statistics.Tools.Mean(this.trainingSet, 0);
this.W = getFeature(this.trainingSet, this.numOfComponents);
// Construct projectedTrainingMatrix
this.projectedTrainingSet = new List <projectedTrainingMatrix>();
for (int i = 0; i < trainingSet.Count(); i++)
{
projectedTrainingMatrix ptm = new projectedTrainingMatrix(this.W.Transpose().Multiply(trainingSet[i].Subtract(meanMatrix).ToArray()), labels[i]);
this.projectedTrainingSet.Add(ptm);
}
}
public PCA(double[][] trainingSet, List<string> labels, int numOfComponents)
{
this.trainingSet = trainingSet;
this.labels = labels;
this.numOfComponents = numOfComponents;
this.meanMatrix = Accord.Statistics.Tools.Mean(this.trainingSet,0);
this.W = getFeature(this.trainingSet, this.numOfComponents);
// Construct projectedTrainingMatrix
this.projectedTrainingSet = new List<projectedTrainingMatrix>();
for (int i = 0; i < trainingSet.Count(); i++)
{
projectedTrainingMatrix ptm = new projectedTrainingMatrix(this.W.Transpose().Multiply(trainingSet[i].Subtract(meanMatrix).ToArray()),labels[i]);
this.projectedTrainingSet.Add(ptm);
}
}
// testFace has been projected to the subspace
static projectedTrainingMatrix[] findKNN(projectedTrainingMatrix[] trainingSet, double[][] testFace, int K, EuclideanDistance metric)
{
int NumOfTrainingSet = trainingSet.Length;
// initialization
projectedTrainingMatrix[] neighbors = new projectedTrainingMatrix[K];
int i;
for (i = 0; i < K; i++)
{
trainingSet[i].distance = metric.getDistance(trainingSet[i].matrix,
testFace);
// System.out.println("index: " + i + " distance: "
// + trainingSet[i].distance);
neighbors[i] = trainingSet[i];
}
// go through the remaining records in the trainingSet to find K nearest
// neighbors
for (i = K; i < NumOfTrainingSet; i++)
{
trainingSet[i].distance = metric.getDistance(trainingSet[i].matrix,
testFace);
// System.out.println("index: " + i + " distance: "
// + trainingSet[i].distance);
int maxIndex = 0;
for (int j = 0; j < K; j++)
{
if (neighbors[j].distance > neighbors[maxIndex].distance)
{
maxIndex = j;
}
}
if (neighbors[maxIndex].distance > trainingSet[i].distance)
{
neighbors[maxIndex] = trainingSet[i];
}
}
return(neighbors);
}
// get the class label by using neighbors
static String classify(projectedTrainingMatrix[] neighbors)
{
Dictionary <String, Double> map = new Dictionary <String, Double>();
int num = neighbors.Length;
for (int index = 0; index < num; index++)
{
projectedTrainingMatrix temp = neighbors[index];
String key = temp.label;
if (!map.ContainsKey(key))
{
map.Add(key, 1 / temp.distance);
}
else
{
double value = map[key];
value += 1 / temp.distance;
map[key] = value;
}
}
// Find the most likely label
double maxSimilarity = 0;
String returnLabel = "";
List <String> labelSet = map.Keys.ToList();
foreach (string label in labelSet)
{
// String label = it.next();
double value = map[label];
if (value > maxSimilarity)
{
maxSimilarity = value;
returnLabel = label;
}
}
return(returnLabel);
}
public LDA(double[][] trainingSet, List<string> labels,int numOfComponents)
{
int n = trainingSet.Length; // sample size
HashSet<String> tempSet = new HashSet<String>(labels);
int c = tempSet.Count; // class size
// process in PCA
PCA pca = new PCA(trainingSet, labels, n - c);
// classify
double[][] meanTotal = new double[n - c][];
for (int i = 0; i < n - c; i++)
{
meanTotal[i] = new double[1];
}
Dictionary<String, List<double[]>> dict = new Dictionary<String, List<double[]>>();
List<projectedTrainingMatrix> pcaTrain = pca.getProjectedTrainingSet();
for (int i = 0; i < pcaTrain.Count; i++) {
String key = pcaTrain[i].label;
meanTotal= meanTotal.Add(pcaTrain[i].matrix);
if (!dict.ContainsKey(key)) {
List<double[]> temp = new List<double[]>();
temp.Add(pcaTrain[i].matrix.Transpose()[0]);
dict.Add(key, temp);
} else {
List<double[]> temp = dict[key];
temp.Add(pcaTrain[i].matrix.Transpose()[0]);
dict[key]= temp;
}
}
meanTotal.ToMatrix().Multiply((double) 1 / n);
// calculate Sw, Sb
double[][] Sw = new double[n - c][];
double[][] Sb = new double[n - c][];
for (int i = 0; i < n - c; i++)
{
Sw[i] = new double[n-c];
Sb[i] = new double[n-c];
}
List<String> labelSet = dict.Keys.ToList();
foreach(string label in labelSet)
{
List<double[]> tempMatrix = dict[label];
double[][] matrixWithinThatClass = tempMatrix.ToArray();
double[] meanOfCurrentClass = Accord.Statistics.Tools.Mean(matrixWithinThatClass);
for (int i = 0; i < matrixWithinThatClass.Length; i++) {
double[][] temp1 = matrixWithinThatClass[i].ToArray().Subtract(meanOfCurrentClass.ToArray());
temp1 = temp1.Multiply(temp1.Transpose());
Sw =Sw.Add(temp1);
}
double[][] temp = meanOfCurrentClass.ToArray().Subtract(meanTotal);
temp = temp.Multiply(temp.Transpose()).ToMatrix().Multiply((double)matrixWithinThatClass.Length).ToArray();
Sb=Sb.Add(temp);
}
// calculate the eigenvalues and vectors of Sw^-1 * Sb
double [][] targetForEigen = Sw.Inverse().Multiply(Sb);
var feature = new EigenvalueDecomposition(targetForEigen.ToMatrix());
double[] d = feature.RealEigenvalues;
int[] indexes;
d.StableSort(out indexes);
indexes = indexes.Reverse().ToArray();
indexes = indexes.Submatrix(0, c - 1);
//int[] indexes = getIndexesOfKEigenvalues(d, c - 1);
double[][] eigenVectors = feature.Eigenvectors.ToArray();
double[][] selectedEigenVectors = eigenVectors.Submatrix(0, eigenVectors.Length - 1, indexes);
this.W = pca.getW().Multiply(selectedEigenVectors);
// Construct projectedTrainingMatrix
this.projectedTrainingSet = new List<projectedTrainingMatrix>();
for (int i = 0; i < trainingSet.Length; i++) {
projectedTrainingMatrix ptm = new projectedTrainingMatrix(this.W.Transpose().Multiply(trainingSet[i].Subtract(pca.meanMatrix).ToArray()), labels[i]);
this.projectedTrainingSet.Add(ptm);
}
this.meanMatrix= pca.meanMatrix;
GC.Collect();
}
public LDA(double[][] trainingSet, List <string> labels, int numOfComponents)
{
int n = trainingSet.Length; // sample size
HashSet <String> tempSet = new HashSet <String>(labels);
int c = tempSet.Count; // class size
// process in PCA
PCA pca = new PCA(trainingSet, labels, n - c);
// classify
double[][] meanTotal = new double[n - c][];
for (int i = 0; i < n - c; i++)
{
meanTotal[i] = new double[1];
}
Dictionary <String, List <double[]> > dict = new Dictionary <String, List <double[]> >();
List <projectedTrainingMatrix> pcaTrain = pca.getProjectedTrainingSet();
for (int i = 0; i < pcaTrain.Count; i++)
{
String key = pcaTrain[i].label;
meanTotal = meanTotal.Add(pcaTrain[i].matrix);
if (!dict.ContainsKey(key))
{
List <double[]> temp = new List <double[]>();
temp.Add(pcaTrain[i].matrix.Transpose()[0]);
dict.Add(key, temp);
}
else
{
List <double[]> temp = dict[key];
temp.Add(pcaTrain[i].matrix.Transpose()[0]);
dict[key] = temp;
}
}
meanTotal.ToMatrix().Multiply((double)1 / n);
// calculate Sw, Sb
double[][] Sw = new double[n - c][];
double[][] Sb = new double[n - c][];
for (int i = 0; i < n - c; i++)
{
Sw[i] = new double[n - c];
Sb[i] = new double[n - c];
}
List <String> labelSet = dict.Keys.ToList();
foreach (string label in labelSet)
{
List <double[]> tempMatrix = dict[label];
double[][] matrixWithinThatClass = tempMatrix.ToArray();
double[] meanOfCurrentClass = Accord.Statistics.Tools.Mean(matrixWithinThatClass);
for (int i = 0; i < matrixWithinThatClass.Length; i++)
{
double[][] temp1 = matrixWithinThatClass[i].ToArray().Subtract(meanOfCurrentClass.ToArray());
temp1 = temp1.Multiply(temp1.Transpose());
Sw = Sw.Add(temp1);
}
double[][] temp = meanOfCurrentClass.ToArray().Subtract(meanTotal);
temp = temp.Multiply(temp.Transpose()).ToMatrix().Multiply((double)matrixWithinThatClass.Length).ToArray();
Sb = Sb.Add(temp);
}
// calculate the eigenvalues and vectors of Sw^-1 * Sb
double [][] targetForEigen = Sw.Inverse().Multiply(Sb);
var feature = new EigenvalueDecomposition(targetForEigen.ToMatrix());
double[] d = feature.RealEigenvalues;
int[] indexes;
d.StableSort(out indexes);
indexes = indexes.Reverse().ToArray();
indexes = indexes.Submatrix(0, c - 1);
//int[] indexes = getIndexesOfKEigenvalues(d, c - 1);
double[][] eigenVectors = feature.Eigenvectors.ToArray();
double[][] selectedEigenVectors = eigenVectors.Submatrix(0, eigenVectors.Length - 1, indexes);
this.W = pca.getW().Multiply(selectedEigenVectors);
// Construct projectedTrainingMatrix
this.projectedTrainingSet = new List <projectedTrainingMatrix>();
for (int i = 0; i < trainingSet.Length; i++)
{
projectedTrainingMatrix ptm = new projectedTrainingMatrix(this.W.Transpose().Multiply(trainingSet[i].Subtract(pca.meanMatrix).ToArray()), labels[i]);
this.projectedTrainingSet.Add(ptm);
}
this.meanMatrix = pca.meanMatrix;
GC.Collect();
}
